I had smartmontools tell me every now and then that a sector of one of the WD Black in the RAID1 mirror was bad. Often the system was slow and the CPU idling. What I have come up with is that the NVMe SSD throttled down when getting hot. Not good when used as a cache. Also a faulty drive is bound to cause issues.

I have now upgraded two WD Black to three WD Red, new chassis to be able to house them and I utilized my old 3Ware RAID controller.

I first went with LVM Thin Provisioning but when the volume has to grow all the time it was also really slow. I reinstalled with ordinary LVM. The VMs are still on a XFS volume as QCOW2 files but that is to be migrates. I attached an LVM volume to a VM and tested performance. I get near gigabit speeds over CIFS from that volume.

Sometimes the version of a package available on CentOS is too old and you really want the latest but you don’t want to manually update it by compiling from source and tracking the upstream. Fortunately there are people that does this for you. Head over to the IUS Community Project and install their RPMs.

A mission of trance

Say you are on a mission. A mission to spread your trance music. So you create a software for this trance mission. And for fun you call it transmission. This software is run in the background. This is called daemonizing in Linux. So you obviously call the executable for this software transmission-daemon. And to keep it from taking over your system you have it running as a dedicated user called transmission.

Evil corp wants you dead

Not all people like your trance music and try to shut you down. So naturally you want to mask your transmission-daemon behind a VPN service. But to not reveal that it is you who are running the transmission you only want the transmission traffic to exit via the VPN tunnel and the rest of your traffic to exit via your normal way.

Our setup

In this example we are using Azire VPN provider. We have our transmission-daemon running on Fedora Linux 24. We will be using OpenVPN for the tunneling. So sign up for a VPN and get the ovpn-file.

Install all the things

# dnf install openvpn transmission-daemon

Yup that’s it

Configure OpenVPN

Copy your ovpn file to /etc/openvpn and name it AzireVPN-SE.conf. It is important that the file ends with .conf.

Keep the motor running

Sometimes the tunnel goes down and the transmission-daemon with it. You can have systemd restart it when that happens by editing /lib/systemd/system/openvpn@.service and adding the following line to the [Service] section